An ice cream mixing apparatus for mixing ice cream with one or more flavor additives comprises a funnel for holding the ice cream and the flavor additives, an auger with a spindle for creating a mixing action, an auger driver for rotating the auger spindle, and a linear actuator for relative movement of the funnel and auger into a position in which the auger is telescoped into the funnel, in which position a rotation of the auger will mix the ice cream and the flavor additives.
The ice cream will normally be in hard form, while the flavor additives may be fruits or nuts. The result of such a mixing is a semiliquid ice cream in which the flavor additives are more or less distributed, which may be sold to consumers.
Such apparatuses are known from a number of patents. U.S. Pat. No. 4,548 054, U.S. Pat. No. 4,637,221, U.S. Pat. No. 4,708,489 and U.S. Pat. No. 4,974,965 all describe machines or apparatuses comprising an auger or agitator with a helical thread or cutter extending into a funnel or container for holding the ice cream and additives. The auger and funnel are relatively rotatable, and after some rotation the ice cream and additives have obtained a semiliquid condition which is attractive to consumers.
All these apparatuses are however encumbered with the drawback that after some use bacteriological growth will take place, which may constitute a health risk to the consumer. To prevent this bacteriological growth manual washing is required, which is time consuming and encumbered with the drawback that the result depend very much of the care of the operator.
U.S. Pat. No. 4,637,221 describes a rinsing process in which the operator by activating a switch can initiate a rinsing of the auger and funnel by tap water. The purpose of the rinsing is to remove residues of ice cream to prevent intermixing of flavors. The activating is manual, and thus the intervals between each rinsing is dependent upon the operator.
Modern health regulations require the bacteriological level to be below certain maximum values, which cannot be assured with prior art ice cream mixing apparatuses. Prior art ice cream mixing apparatuses are thus unsuitable in areas where such regulations apply.
The object of the invention is to provide an ice cream mixing apparatus for mixing ice cream with one or more flavor additives, in which the bacteriological level can be kept below a certain maximum value. The object is further that the bacteriological level shall be kept below the certain maximum value independent of the operator. The object is further that the ice cream mixing apparatus shall also comprise means for preventing intermixing of different flavor additives without having to initiate a thorough and time consuming complete washing.
The invention thus has an ice cream mixing apparatus for mixing ice cream with one or more flavor additives, comprising a funnel for holding the ice cream and the flavor additives, an auger with a spindle for creating a mixing action, an auger driver for rotating the auger spindle, and a linear actuator for relative movement of the funnel and auger into a position in which the auger is telescoped into the funnel, in which position a rotation of the auger will mix the ice cream and the flavor additives. The funnel forms part of an enclosure with a closable inlet for the ice cream and at least one spray nozzle for pointing a water spray at the auger for washing purposes. Further the auger or the auger spindle has at least one vane in an area which will be hit by the water spray during the relative movement of the funnel and auger, causing a deflection of the water spray. This spraying may take place during a period when the mixing apparatus is not used for mixing ice cream.
Preferably the at least one vane is located in or adjacent to a transition area between the auger and the auger spindle. The vane or vanes have surfaces which direct the water spray towards the auger spindle and the ice cream inlet, and in order to enable a thorough spraying of internal parts of the funnel, there should preferably be more than one vane. The vanes may be formed by a vane wheel, which may be mounted on the auger spindle.
Preferably the water supply to the spray nozzle includes a heated water supply, with temperature between 40xc2x0 C. and 75xc2x0 C., preferably between 50xc2x0 C. and 70xc2x0 C. and most preferred between 60xc2x0 C. and 65xc2x0 C., as this has been found to be most beneficial for removing ice cream residues without causing the ice cream residues to coagulate. The heated water spraying removes residue ice cream from the funnel and provides a thorough washing in which bacteria and the basis for bacteriological growth are removed, thereby keeping the bacteriological level below a certain maximum value. The heated water supply may be achieved by a connection to a hot water tap, or a separate heater which heats cold water.
A cold water supply as well as a liquid detergent supply may also be included in the supply to the spray nozzle. The liquid detergent may be sprayed on the aiuger and funnel prior to, together with or in between the heated water spraying, which enhances the washing and further reduces the bacteriological level.
Electric circuitry comprising switches and control valves may be used for manually or automatically controlling the supply to the at least one spray nozzle. This electric circuitry preferably forms part of a control system comprising an electronic control unit, a power supply and a control panel with control buttons and control lights, for controlling electrical equipment.
The control system may initiate a heated water spraying on a regular timer basis by a timer in the electronic control unit. Preferably a complete washing sequence as a minimum comprising a cold water spraying, a liquid detergent spraying and a heated water spraying is initiated on a regular timer basis. Thereby the washing function is independent of the operator.
A cold water spraying, i.e. a rinsing of the funnel, may be initiated manually between mixing of ice cream with different flavor additives. The cold water spraying may be of a shorter duration than the complete washing, yet the cold water spraying will be sufficient to remove enough residues in the funnel to prevent intermixing of ice cream with different flavors.
The auger driver may be adapted to rotate the auger spindle at variable speeds, e.g. two different speeds, enabling a fast rotation of the auger when there are no or little resistance to the rotation, and a slow rotation of the auger when there is a resistance to the rotation caused by the ice cream.
Further scope of the applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, science various changes and modifications within the spirit and scops of the invention will become apparent to those skilled in the art from this detailed description.